diff options
Diffstat (limited to 'lib/Kconfig.debug')
| -rw-r--r-- | lib/Kconfig.debug | 2028 |
1 files changed, 1482 insertions, 546 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index cbdfae379896..ef36b829ae1f 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -35,6 +35,17 @@ config PRINTK_CALLER no option to enable/disable at the kernel command line parameter or sysfs interface. +config STACKTRACE_BUILD_ID + bool "Show build ID information in stacktraces" + depends on PRINTK + help + Selecting this option adds build ID information for symbols in + stacktraces printed with the printk format '%p[SR]b'. + + This option is intended for distros where debuginfo is not easily + accessible but can be downloaded given the build ID of the vmlinux or + kernel module where the function is located. + config CONSOLE_LOGLEVEL_DEFAULT int "Default console loglevel (1-15)" range 1 15 @@ -98,7 +109,8 @@ config DYNAMIC_DEBUG bool "Enable dynamic printk() support" default n depends on PRINTK - depends on DEBUG_FS + depends on (DEBUG_FS || PROC_FS) + select DYNAMIC_DEBUG_CORE help Compiles debug level messages into the kernel, which would not @@ -116,8 +128,9 @@ config DYNAMIC_DEBUG Usage: Dynamic debugging is controlled via the 'dynamic_debug/control' file, - which is contained in the 'debugfs' filesystem. Thus, the debugfs - filesystem must first be mounted before making use of this feature. + which is contained in the 'debugfs' filesystem or procfs. + Thus, the debugfs or procfs filesystem must first be mounted before + making use of this feature. We refer the control file as: <debugfs>/dynamic_debug/control. This file contains a list of the debug statements that can be enabled. The format for each line of the file is: @@ -128,8 +141,8 @@ config DYNAMIC_DEBUG lineno : line number of the debug statement module : module that contains the debug statement function : function that contains the debug statement - flags : '=p' means the line is turned 'on' for printing - format : the format used for the debug statement + flags : '=p' means the line is turned 'on' for printing + format : the format used for the debug statement From a live system: @@ -164,26 +177,133 @@ config DYNAMIC_DEBUG See Documentation/admin-guide/dynamic-debug-howto.rst for additional information. +config DYNAMIC_DEBUG_CORE + bool "Enable core function of dynamic debug support" + depends on PRINTK + depends on (DEBUG_FS || PROC_FS) + help + Enable core functional support of dynamic debug. It is useful + when you want to tie dynamic debug to your kernel modules with + DYNAMIC_DEBUG_MODULE defined for each of them, especially for + the case of embedded system where the kernel image size is + sensitive for people. + +config SYMBOLIC_ERRNAME + bool "Support symbolic error names in printf" + default y if PRINTK + help + If you say Y here, the kernel's printf implementation will + be able to print symbolic error names such as ENOSPC instead + of the number 28. It makes the kernel image slightly larger + (about 3KB), but can make the kernel logs easier to read. + +config DEBUG_BUGVERBOSE + bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT + depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE) + default y + help + Say Y here to make BUG() panics output the file name and line number + of the BUG call as well as the EIP and oops trace. This aids + debugging but costs about 70-100K of memory. + endmenu # "printk and dmesg options" +config DEBUG_KERNEL + bool "Kernel debugging" + help + Say Y here if you are developing drivers or trying to debug and + identify kernel problems. + +config DEBUG_MISC + bool "Miscellaneous debug code" + default DEBUG_KERNEL + depends on DEBUG_KERNEL + help + Say Y here if you need to enable miscellaneous debug code that should + be under a more specific debug option but isn't. + menu "Compile-time checks and compiler options" config DEBUG_INFO - bool "Compile the kernel with debug info" - depends on DEBUG_KERNEL && !COMPILE_TEST + bool help - If you say Y here the resulting kernel image will include - debugging info resulting in a larger kernel image. + A kernel debug info option other than "None" has been selected + in the "Debug information" choice below, indicating that debug + information will be generated for build targets. + +# Clang generates .uleb128 with label differences for DWARF v5, a feature that +# older binutils ports do not support when utilizing RISC-V style linker +# relaxation: https://sourceware.org/bugzilla/show_bug.cgi?id=27215 +config AS_HAS_NON_CONST_ULEB128 + def_bool $(as-instr,.uleb128 .Lexpr_end4 - .Lexpr_start3\n.Lexpr_start3:\n.Lexpr_end4:) + +choice + prompt "Debug information" + depends on DEBUG_KERNEL + help + Selecting something other than "None" results in a kernel image + that will include debugging info resulting in a larger kernel image. This adds debug symbols to the kernel and modules (gcc -g), and is needed if you intend to use kernel crashdump or binary object tools like crash, kgdb, LKCD, gdb, etc on the kernel. - Say Y here only if you plan to debug the kernel. - If unsure, say N. + Choose which version of DWARF debug info to emit. If unsure, + select "Toolchain default". + +config DEBUG_INFO_NONE + bool "Disable debug information" + help + Do not build the kernel with debugging information, which will + result in a faster and smaller build. + +config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT + bool "Rely on the toolchain's implicit default DWARF version" + select DEBUG_INFO + depends on !CC_IS_CLANG || AS_IS_LLVM || CLANG_VERSION < 140000 || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_ULEB128) + help + The implicit default version of DWARF debug info produced by a + toolchain changes over time. + + This can break consumers of the debug info that haven't upgraded to + support newer revisions, and prevent testing newer versions, but + those should be less common scenarios. + +config DEBUG_INFO_DWARF4 + bool "Generate DWARF Version 4 debuginfo" + select DEBUG_INFO + depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502) + help + Generate DWARF v4 debug info. This requires gcc 4.5+, binutils 2.35.2 + if using clang without clang's integrated assembler, and gdb 7.0+. + + If you have consumers of DWARF debug info that are not ready for + newer revisions of DWARF, you may wish to choose this or have your + config select this. + +config DEBUG_INFO_DWARF5 + bool "Generate DWARF Version 5 debuginfo" + select DEBUG_INFO + depends on !ARCH_HAS_BROKEN_DWARF5 + depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_ULEB128) + help + Generate DWARF v5 debug info. Requires binutils 2.35.2, gcc 5.0+ (gcc + 5.0+ accepts the -gdwarf-5 flag but only had partial support for some + draft features until 7.0), and gdb 8.0+. + + Changes to the structure of debug info in Version 5 allow for around + 15-18% savings in resulting image and debug info section sizes as + compared to DWARF Version 4. DWARF Version 5 standardizes previous + extensions such as accelerators for symbol indexing and the format + for fission (.dwo/.dwp) files. Users may not want to select this + config if they rely on tooling that has not yet been updated to + support DWARF Version 5. + +endchoice # "Debug information" + +if DEBUG_INFO config DEBUG_INFO_REDUCED bool "Reduce debugging information" - depends on DEBUG_INFO help If you say Y here gcc is instructed to generate less debugging information for structure types. This means that tools that @@ -194,10 +314,54 @@ config DEBUG_INFO_REDUCED DEBUG_INFO build and compile times are reduced too. Only works with newer gcc versions. +choice + prompt "Compressed Debug information" + help + Compress the resulting debug info. Results in smaller debug info sections, + but requires that consumers are able to decompress the results. + + If unsure, choose DEBUG_INFO_COMPRESSED_NONE. + +config DEBUG_INFO_COMPRESSED_NONE + bool "Don't compress debug information" + help + Don't compress debug info sections. + +config DEBUG_INFO_COMPRESSED_ZLIB + bool "Compress debugging information with zlib" + depends on $(cc-option,-gz=zlib) + depends on $(ld-option,--compress-debug-sections=zlib) + help + Compress the debug information using zlib. Requires GCC 5.0+ or Clang + 5.0+, binutils 2.26+, and zlib. + + Users of dpkg-deb via scripts/package/builddeb may find an increase in + size of their debug .deb packages with this config set, due to the + debug info being compressed with zlib, then the object files being + recompressed with a different compression scheme. But this is still + preferable to setting $KDEB_COMPRESS to "none" which would be even + larger. + +config DEBUG_INFO_COMPRESSED_ZSTD + bool "Compress debugging information with zstd" + depends on $(cc-option,-gz=zstd) + depends on $(ld-option,--compress-debug-sections=zstd) + help + Compress the debug information using zstd. This may provide better + compression than zlib, for about the same time costs, but requires newer + toolchain support. Requires GCC 13.0+ or Clang 16.0+, binutils 2.40+, and + zstd. + +endchoice # "Compressed Debug information" + config DEBUG_INFO_SPLIT bool "Produce split debuginfo in .dwo files" - depends on DEBUG_INFO depends on $(cc-option,-gsplit-dwarf) + # RISC-V linker relaxation + -gsplit-dwarf has issues with LLVM and GCC + # prior to 12.x: + # https://github.com/llvm/llvm-project/issues/56642 + # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99090 + depends on !RISCV || GCC_VERSION >= 120000 help Generate debug info into separate .dwo files. This significantly reduces the build directory size for builds with DEBUG_INFO, @@ -210,27 +374,57 @@ config DEBUG_INFO_SPLIT to know about the .dwo files and include them. Incompatible with older versions of ccache. -config DEBUG_INFO_DWARF4 - bool "Generate dwarf4 debuginfo" - depends on DEBUG_INFO - depends on $(cc-option,-gdwarf-4) - help - Generate dwarf4 debug info. This requires recent versions - of gcc and gdb. It makes the debug information larger. - But it significantly improves the success of resolving - variables in gdb on optimized code. - config DEBUG_INFO_BTF bool "Generate BTF typeinfo" - depends on DEBUG_INFO + depends on !DEBUG_INFO_SPLIT && !DEBUG_INFO_REDUCED + depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST + depends on BPF_SYSCALL + depends on !DEBUG_INFO_DWARF5 || PAHOLE_VERSION >= 121 + # pahole uses elfutils, which does not have support for Hexagon relocations + depends on !HEXAGON help Generate deduplicated BTF type information from DWARF debug info. Turning this on expects presence of pahole tool, which will convert DWARF type info into equivalent deduplicated BTF type info. +config PAHOLE_HAS_SPLIT_BTF + def_bool PAHOLE_VERSION >= 119 + +config PAHOLE_HAS_BTF_TAG + def_bool PAHOLE_VERSION >= 123 + depends on CC_IS_CLANG + help + Decide whether pahole emits btf_tag attributes (btf_type_tag and + btf_decl_tag) or not. Currently only clang compiler implements + these attributes, so make the config depend on CC_IS_CLANG. + +config PAHOLE_HAS_LANG_EXCLUDE + def_bool PAHOLE_VERSION >= 124 + help + Support for the --lang_exclude flag which makes pahole exclude + compilation units from the supplied language. Used in Kbuild to + omit Rust CUs which are not supported in version 1.24 of pahole, + otherwise it would emit malformed kernel and module binaries when + using DEBUG_INFO_BTF_MODULES. + +config DEBUG_INFO_BTF_MODULES + def_bool y + depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF + help + Generate compact split BTF type information for kernel modules. + +config MODULE_ALLOW_BTF_MISMATCH + bool "Allow loading modules with non-matching BTF type info" + depends on DEBUG_INFO_BTF_MODULES + help + For modules whose split BTF does not match vmlinux, load without + BTF rather than refusing to load. The default behavior with + module BTF enabled is to reject modules with such mismatches; + this option will still load module BTF where possible but ignore + it when a mismatch is found. + config GDB_SCRIPTS bool "Provide GDB scripts for kernel debugging" - depends on DEBUG_INFO help This creates the required links to GDB helper scripts in the build directory. If you load vmlinux into gdb, the helper @@ -239,26 +433,22 @@ config GDB_SCRIPTS instance. See Documentation/dev-tools/gdb-kernel-debugging.rst for further details. -config ENABLE_MUST_CHECK - bool "Enable __must_check logic" - default y - help - Enable the __must_check logic in the kernel build. Disable this to - suppress the "warning: ignoring return value of 'foo', declared with - attribute warn_unused_result" messages. +endif # DEBUG_INFO config FRAME_WARN - int "Warn for stack frames larger than (needs gcc 4.4)" + int "Warn for stack frames larger than" range 0 8192 + default 0 if KMSAN default 2048 if GCC_PLUGIN_LATENT_ENTROPY - default 1280 if (!64BIT && PARISC) - default 1024 if (!64BIT && !PARISC) + default 2048 if PARISC + default 1536 if (!64BIT && XTENSA) + default 1280 if KASAN && !64BIT + default 1024 if !64BIT default 2048 if 64BIT help - Tell gcc to warn at build time for stack frames larger than this. + Tell the compiler to warn at build time for stack frames larger than this. Setting this too low will cause a lot of warnings. Setting it to 0 disables the warning. - Requires gcc 4.4 config STRIP_ASM_SYMS bool "Strip assembler-generated symbols during link" @@ -269,72 +459,28 @@ config STRIP_ASM_SYMS get_wchan() and suchlike. config READABLE_ASM - bool "Generate readable assembler code" - depends on DEBUG_KERNEL - help - Disable some compiler optimizations that tend to generate human unreadable - assembler output. This may make the kernel slightly slower, but it helps - to keep kernel developers who have to stare a lot at assembler listings - sane. - -config UNUSED_SYMBOLS - bool "Enable unused/obsolete exported symbols" - default y if X86 - help - Unused but exported symbols make the kernel needlessly bigger. For - that reason most of these unused exports will soon be removed. This - option is provided temporarily to provide a transition period in case - some external kernel module needs one of these symbols anyway. If you - encounter such a case in your module, consider if you are actually - using the right API. (rationale: since nobody in the kernel is using - this in a module, there is a pretty good chance it's actually the - wrong interface to use). If you really need the symbol, please send a - mail to the linux kernel mailing list mentioning the symbol and why - you really need it, and what the merge plan to the mainline kernel for - your module is. - -config DEBUG_FS - bool "Debug Filesystem" + bool "Generate readable assembler code" + depends on DEBUG_KERNEL + depends on CC_IS_GCC help - debugfs is a virtual file system that kernel developers use to put - debugging files into. Enable this option to be able to read and - write to these files. - - For detailed documentation on the debugfs API, see - Documentation/filesystems/. - - If unsure, say N. + Disable some compiler optimizations that tend to generate human unreadable + assembler output. This may make the kernel slightly slower, but it helps + to keep kernel developers who have to stare a lot at assembler listings + sane. -config HEADERS_CHECK - bool "Run 'make headers_check' when building vmlinux" +config HEADERS_INSTALL + bool "Install uapi headers to usr/include" depends on !UML help - This option will extract the user-visible kernel headers whenever - building the kernel, and will run basic sanity checks on them to - ensure that exported files do not attempt to include files which - were not exported, etc. - - If you're making modifications to header files which are - relevant for userspace, say 'Y', and check the headers - exported to $(INSTALL_HDR_PATH) (usually 'usr/include' in - your build tree), to make sure they're suitable. - -config OPTIMIZE_INLINING - bool "Allow compiler to uninline functions marked 'inline'" - help - This option determines if the kernel forces gcc to inline the functions - developers have marked 'inline'. Doing so takes away freedom from gcc to - do what it thinks is best, which is desirable for the gcc 3.x series of - compilers. The gcc 4.x series have a rewritten inlining algorithm and - enabling this option will generate a smaller kernel there. Hopefully - this algorithm is so good that allowing gcc 4.x and above to make the - decision will become the default in the future. Until then this option - is there to test gcc for this. - - If unsure, say N. + This option will install uapi headers (headers exported to user-space) + into the usr/include directory for use during the kernel build. + This is unneeded for building the kernel itself, but needed for some + user-space program samples. It is also needed by some features such + as uapi header sanity checks. config DEBUG_SECTION_MISMATCH bool "Enable full Section mismatch analysis" + depends on CC_IS_GCC help The section mismatch analysis checks if there are illegal references from one section to another section. @@ -346,23 +492,13 @@ config DEBUG_SECTION_MISMATCH which results in the code/data being placed in specific sections. The section mismatch analysis is always performed after a full kernel build, and enabling this option causes the following - additional steps to occur: + additional step to occur: - Add the option -fno-inline-functions-called-once to gcc commands. When inlining a function annotated with __init in a non-init function, we would lose the section information and thus the analysis would not catch the illegal reference. This option tells gcc to inline less (but it does result in a larger kernel). - - Run the section mismatch analysis for each module/built-in.a file. - When we run the section mismatch analysis on vmlinux.o, we - lose valuable information about where the mismatch was - introduced. - Running the analysis for each module/built-in.a file - tells where the mismatch happens much closer to the - source. The drawback is that the same mismatch is - reported at least twice. - - Enable verbose reporting from modpost in order to help resolve - the section mismatches that are reported. config SECTION_MISMATCH_WARN_ONLY bool "Make section mismatch errors non-fatal" @@ -373,6 +509,19 @@ config SECTION_MISMATCH_WARN_ONLY If unsure, say Y. +config DEBUG_FORCE_FUNCTION_ALIGN_64B + bool "Force all function address 64B aligned" + depends on EXPERT && (X86_64 || ARM64 || PPC32 || PPC64 || ARC || RISCV || S390) + select FUNCTION_ALIGNMENT_64B + help + There are cases that a commit from one domain changes the function + address alignment of other domains, and cause magic performance + bump (regression or improvement). Enable this option will help to + verify if the bump is caused by function alignment changes, while + it will slightly increase the kernel size and affect icache usage. + + It is mainly for debug and performance tuning use. + # # Select this config option from the architecture Kconfig, if it # is preferred to always offer frame pointers as a config @@ -390,20 +539,36 @@ config FRAME_POINTER larger and slower, but it gives very useful debugging information in case of kernel bugs. (precise oopses/stacktraces/warnings) +config OBJTOOL + bool + config STACK_VALIDATION bool "Compile-time stack metadata validation" - depends on HAVE_STACK_VALIDATION + depends on HAVE_STACK_VALIDATION && UNWINDER_FRAME_POINTER + select OBJTOOL default n help - Add compile-time checks to validate stack metadata, including frame - pointers (if CONFIG_FRAME_POINTER is enabled). This helps ensure - that runtime stack traces are more reliable. - - This is also a prerequisite for generation of ORC unwind data, which - is needed for CONFIG_UNWINDER_ORC. + Validate frame pointer rules at compile-time. This helps ensure that + runtime stack traces are more reliable. For more information, see - tools/objtool/Documentation/stack-validation.txt. + tools/objtool/Documentation/objtool.txt. + +config NOINSTR_VALIDATION + bool + depends on HAVE_NOINSTR_VALIDATION && DEBUG_ENTRY + select OBJTOOL + default y + +config VMLINUX_MAP + bool "Generate vmlinux.map file when linking" + depends on EXPERT + help + Selecting this option will pass "-Map=vmlinux.map" to ld + when linking vmlinux. That file can be useful for verifying + and debugging magic section games, and for seeing which + pieces of code get eliminated with + CONFIG_LD_DEAD_CODE_DATA_ELIMINATION. config DEBUG_FORCE_WEAK_PER_CPU bool "Force weak per-cpu definitions" @@ -422,6 +587,8 @@ config DEBUG_FORCE_WEAK_PER_CPU endmenu # "Compiler options" +menu "Generic Kernel Debugging Instruments" + config MAGIC_SYSRQ bool "Magic SysRq key" depends on !UML @@ -455,20 +622,71 @@ config MAGIC_SYSRQ_SERIAL This option allows you to decide whether you want to enable the magic SysRq key. -config DEBUG_KERNEL - bool "Kernel debugging" +config MAGIC_SYSRQ_SERIAL_SEQUENCE + string "Char sequence that enables magic SysRq over serial" + depends on MAGIC_SYSRQ_SERIAL + default "" help - Say Y here if you are developing drivers or trying to debug and - identify kernel problems. + Specifies a sequence of characters that can follow BREAK to enable + SysRq on a serial console. -config DEBUG_MISC - bool "Miscellaneous debug code" - default DEBUG_KERNEL - depends on DEBUG_KERNEL + If unsure, leave an empty string and the option will not be enabled. + +config DEBUG_FS + bool "Debug Filesystem" help - Say Y here if you need to enable miscellaneous debug code that should - be under a more specific debug option but isn't. + debugfs is a virtual file system that kernel developers use to put + debugging files into. Enable this option to be able to read and + write to these files. + + For detailed documentation on the debugfs API, see + Documentation/filesystems/. + + If unsure, say N. + +choice + prompt "Debugfs default access" + depends on DEBUG_FS + default DEBUG_FS_ALLOW_ALL + help + This selects the default access restrictions for debugfs. + It can be overridden with kernel command line option + debugfs=[on,no-mount,off]. The restrictions apply for API access + and filesystem registration. + +config DEBUG_FS_ALLOW_ALL + bool "Access normal" + help + No restrictions apply. Both API and filesystem registration + is on. This is the normal default operation. + +config DEBUG_FS_DISALLOW_MOUNT + bool "Do not register debugfs as filesystem" + help + The API is open but filesystem is not loaded. Clients can still do + their work and read with debug tools that do not need + debugfs filesystem. + +config DEBUG_FS_ALLOW_NONE + bool "No access" + help + Access is off. Clients get -PERM when trying to create nodes in + debugfs tree and debugfs is not registered as a filesystem. + Client can then back-off or continue without debugfs access. + +endchoice + +source "lib/Kconfig.kgdb" +source "lib/Kconfig.ubsan" +source "lib/Kconfig.kcsan" +endmenu + +menu "Networking Debugging" + +source "net/Kconfig.debug" + +endmenu # "Networking Debugging" menu "Memory Debugging" @@ -529,139 +747,77 @@ config DEBUG_OBJECTS_PERCPU_COUNTER config DEBUG_OBJECTS_ENABLE_DEFAULT int "debug_objects bootup default value (0-1)" - range 0 1 - default "1" - depends on DEBUG_OBJECTS - help - Debug objects boot parameter default value - -config DEBUG_SLAB - bool "Debug slab memory allocations" - depends on DEBUG_KERNEL && SLAB - help - Say Y here to have the kernel do limited verification on memory - allocation as well as poisoning memory on free to catch use of freed - memory. This can make kmalloc/kfree-intensive workloads much slower. - -config SLUB_DEBUG_ON - bool "SLUB debugging on by default" - depends on SLUB && SLUB_DEBUG - default n - help - Boot with debugging on by default. SLUB boots by default with - the runtime debug capabilities switched off. Enabling this is - equivalent to specifying the "slub_debug" parameter on boot. - There is no support for more fine grained debug control like - possible with slub_debug=xxx. SLUB debugging may be switched - off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying - "slub_debug=-". - -config SLUB_STATS - default n - bool "Enable SLUB performance statistics" - depends on SLUB && SYSFS - help - SLUB statistics are useful to debug SLUBs allocation behavior in - order find ways to optimize the allocator. This should never be - enabled for production use since keeping statistics slows down - the allocator by a few percentage points. The slabinfo command - supports the determination of the most active slabs to figure - out which slabs are relevant to a particular load. - Try running: slabinfo -DA - -config HAVE_DEBUG_KMEMLEAK - bool - -config DEBUG_KMEMLEAK - bool "Kernel memory leak detector" - depends on DEBUG_KERNEL && HAVE_DEBUG_KMEMLEAK - select DEBUG_FS - select STACKTRACE if STACKTRACE_SUPPORT - select KALLSYMS - select CRC32 - help - Say Y here if you want to enable the memory leak - detector. The memory allocation/freeing is traced in a way - similar to the Boehm's conservative garbage collector, the - difference being that the orphan objects are not freed but - only shown in /sys/kernel/debug/kmemleak. Enabling this - feature will introduce an overhead to memory - allocations. See Documentation/dev-tools/kmemleak.rst for more - details. - - Enabling DEBUG_SLAB or SLUB_DEBUG may increase the chances - of finding leaks due to the slab objects poisoning. - - In order to access the kmemleak file, debugfs needs to be - mounted (usually at /sys/kernel/debug). - -config DEBUG_KMEMLEAK_EARLY_LOG_SIZE - int "Maximum kmemleak early log entries" - depends on DEBUG_KMEMLEAK - range 200 40000 - default 400 - help - Kmemleak must track all the memory allocations to avoid - reporting false positives. Since memory may be allocated or - freed before kmemleak is initialised, an early log buffer is - used to store these actions. If kmemleak reports "early log - buffer exceeded", please increase this value. - -config DEBUG_KMEMLEAK_TEST - tristate "Simple test for the kernel memory leak detector" - depends on DEBUG_KMEMLEAK && m - help - This option enables a module that explicitly leaks memory. - - If unsure, say N. - -config DEBUG_KMEMLEAK_DEFAULT_OFF - bool "Default kmemleak to off" - depends on DEBUG_KMEMLEAK + range 0 1 + default "1" + depends on DEBUG_OBJECTS help - Say Y here to disable kmemleak by default. It can then be enabled - on the command line via kmemleak=on. + Debug objects boot parameter default value -config DEBUG_KMEMLEAK_AUTO_SCAN - bool "Enable kmemleak auto scan thread on boot up" - default y - depends on DEBUG_KMEMLEAK +config SHRINKER_DEBUG + bool "Enable shrinker debugging support" + depends on DEBUG_FS help - Depending on the cpu, kmemleak scan may be cpu intensive and can - stall user tasks at times. This option enables/disables automatic - kmemleak scan at boot up. - - Say N here to disable kmemleak auto scan thread to stop automatic - scanning. Disabling this option disables automatic reporting of - memory leaks. - - If unsure, say Y. + Say Y to enable the shrinker debugfs interface which provides + visibility into the kernel memory shrinkers subsystem. + Disable it to avoid an extra memory footprint. config DEBUG_STACK_USAGE bool "Stack utilization instrumentation" - depends on DEBUG_KERNEL && !IA64 + depends on DEBUG_KERNEL help Enables the display of the minimum amount of free stack which each task has ever had available in the sysrq-T and sysrq-P debug output. + Also emits a message to dmesg when a process exits if that process + used more stack space than previously exiting processes. This option will slow down process creation somewhat. +config SCHED_STACK_END_CHECK + bool "Detect stack corruption on calls to schedule()" + depends on DEBUG_KERNEL + default n + help + This option checks for a stack overrun on calls to schedule(). + If the stack end location is found to be over written always panic as + the content of the corrupted region can no longer be trusted. + This is to ensure no erroneous behaviour occurs which could result in + data corruption or a sporadic crash at a later stage once the region + is examined. The runtime overhead introduced is minimal. + +config ARCH_HAS_DEBUG_VM_PGTABLE + bool + help + An architecture should select this when it can successfully + build and run DEBUG_VM_PGTABLE. + +config DEBUG_VM_IRQSOFF + def_bool DEBUG_VM && !PREEMPT_RT + config DEBUG_VM bool "Debug VM" depends on DEBUG_KERNEL help Enable this to turn on extended checks in the virtual-memory system - that may impact performance. + that may impact performance. + + If unsure, say N. + +config DEBUG_VM_SHOOT_LAZIES + bool "Debug MMU_LAZY_TLB_SHOOTDOWN implementation" + depends on DEBUG_VM + depends on MMU_LAZY_TLB_SHOOTDOWN + help + Enable additional IPIs that ensure lazy tlb mm references are removed + before the mm is freed. If unsure, say N. -config DEBUG_VM_VMACACHE - bool "Debug VMA caching" +config DEBUG_VM_MAPLE_TREE + bool "Debug VM maple trees" depends on DEBUG_VM + select DEBUG_MAPLE_TREE help - Enable this to turn on VMA caching debug information. Doing so - can cause significant overhead, so only enable it in non-production - environments. + Enable VM maple tree debugging information and extra validations. If unsure, say N. @@ -681,6 +837,22 @@ config DEBUG_VM_PGFLAGS If unsure, say N. +config DEBUG_VM_PGTABLE + bool "Debug arch page table for semantics compliance" + depends on MMU + depends on ARCH_HAS_DEBUG_VM_PGTABLE + default y if DEBUG_VM + help + This option provides a debug method which can be used to test + architecture page table helper functions on various platforms in + verifying if they comply with expected generic MM semantics. This + will help architecture code in making sure that any changes or + new additions of these helpers still conform to expected + semantics of the generic MM. Platforms will have to opt in for + this through ARCH_HAS_DEBUG_VM_PGTABLE. + + If unsure, say N. + config ARCH_HAS_DEBUG_VIRTUAL bool @@ -714,7 +886,7 @@ config DEBUG_MEMORY_INIT config MEMORY_NOTIFIER_ERROR_INJECT tristate "Memory hotplug notifier error injection module" - depends on MEMORY_HOTPLUG_SPARSE && NOTIFIER_ERROR_INJECTION + depends on MEMORY_HOTPLUG && NOTIFIER_ERROR_INJECTION help This option provides the ability to inject artificial errors to memory hotplug notifier chain callbacks. It is controlled through @@ -746,9 +918,31 @@ config DEBUG_PER_CPU_MAPS Say N if unsure. +config DEBUG_KMAP_LOCAL + bool "Debug kmap_local temporary mappings" + depends on DEBUG_KERNEL && KMAP_LOCAL + help + This option enables additional error checking for the kmap_local + infrastructure. Disable for production use. + +config ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP + bool + +config DEBUG_KMAP_LOCAL_FORCE_MAP + bool "Enforce kmap_local temporary mappings" + depends on DEBUG_KERNEL && ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP + select KMAP_LOCAL + select DEBUG_KMAP_LOCAL + help + This option enforces temporary mappings through the kmap_local + mechanism for non-highmem pages and on non-highmem systems. + Disable this for production systems! + config DEBUG_HIGHMEM bool "Highmem debugging" depends on DEBUG_KERNEL && HIGHMEM + select DEBUG_KMAP_LOCAL_FORCE_MAP if ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP + select DEBUG_KMAP_LOCAL help This option enables additional error checking for high memory systems. Disable for production systems. @@ -759,7 +953,7 @@ config HAVE_DEBUG_STACKOVERFLOW config DEBUG_STACKOVERFLOW bool "Check for stack overflows" depends on DEBUG_KERNEL && HAVE_DEBUG_STACKOVERFLOW - ---help--- + help Say Y here if you want to check for overflows of kernel, IRQ and exception stacks (if your architecture uses them). This option will show detailed messages if free stack space drops @@ -775,66 +969,49 @@ config DEBUG_STACKOVERFLOW If in doubt, say "N". source "lib/Kconfig.kasan" +source "lib/Kconfig.kfence" +source "lib/Kconfig.kmsan" endmenu # "Memory Debugging" -config ARCH_HAS_KCOV - bool +config DEBUG_SHIRQ + bool "Debug shared IRQ handlers" + depends on DEBUG_KERNEL help - An architecture should select this when it can successfully - build and run with CONFIG_KCOV. This typically requires - disabling instrumentation for some early boot code. + Enable this to generate a spurious interrupt just before a shared + interrupt handler is deregistered (generating one when registering + is currently disabled). Drivers need to handle this correctly. Some + don't and need to be caught. -config CC_HAS_SANCOV_TRACE_PC - def_bool $(cc-option,-fsanitize-coverage=trace-pc) +menu "Debug Oops, Lockups and Hangs" -config KCOV - bool "Code coverage for fuzzing" - depends on ARCH_HAS_KCOV - depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS - select DEBUG_FS - select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC +config PANIC_ON_OOPS + bool "Panic on Oops" help - KCOV exposes kernel code coverage information in a form suitable - for coverage-guided fuzzing (randomized testing). - - If RANDOMIZE_BASE is enabled, PC values will not be stable across - different machines and across reboots. If you need stable PC values, - disable RANDOMIZE_BASE. + Say Y here to enable the kernel to panic when it oopses. This + has the same effect as setting oops=panic on the kernel command + line. - For more details, see Documentation/dev-tools/kcov.rst. + This feature is useful to ensure that the kernel does not do + anything erroneous after an oops which could result in data + corruption or other issues. -config KCOV_ENABLE_COMPARISONS - bool "Enable comparison operands collection by KCOV" - depends on KCOV - depends on $(cc-option,-fsanitize-coverage=trace-cmp) - help - KCOV also exposes operands of every comparison in the instrumented - code along with operand sizes and PCs of the comparison instructions. - These operands can be used by fuzzing engines to improve the quality - of fuzzing coverage. + Say N if unsure. -config KCOV_INSTRUMENT_ALL - bool "Instrument all code by default" - depends on KCOV - default y - help - If you are doing generic system call fuzzing (like e.g. syzkaller), - then you will want to instrument the whole kernel and you should - say y here. If you are doing more targeted fuzzing (like e.g. - filesystem fuzzing with AFL) then you will want to enable coverage - for more specific subsets of files, and should say n here. +config PANIC_ON_OOPS_VALUE + int + range 0 1 + default 0 if !PANIC_ON_OOPS + default 1 if PANIC_ON_OOPS -config DEBUG_SHIRQ - bool "Debug shared IRQ handlers" - depends on DEBUG_KERNEL +config PANIC_TIMEOUT + int "panic timeout" + default 0 help - Enable this to generate a spurious interrupt as soon as a shared - interrupt handler is registered, and just before one is deregistered. - Drivers ought to be able to handle interrupts coming in at those - points; some don't and need to be caught. - -menu "Debug Lockups and Hangs" + Set the timeout value (in seconds) until a reboot occurs when + the kernel panics. If n = 0, then we wait forever. A timeout + value n > 0 will wait n seconds before rebooting, while a timeout + value n < 0 will reboot immediately. config LOCKUP_DETECTOR bool @@ -869,35 +1046,30 @@ config BOOTPARAM_SOFTLOCKUP_PANIC Say N if unsure. -config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE - int - depends on SOFTLOCKUP_DETECTOR - range 0 1 - default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC - default 1 if BOOTPARAM_SOFTLOCKUP_PANIC - -config HARDLOCKUP_DETECTOR_PERF +config HAVE_HARDLOCKUP_DETECTOR_BUDDY bool - select SOFTLOCKUP_DETECTOR + depends on SMP + default y # -# Enables a timestamp based low pass filter to compensate for perf based -# hard lockup detection which runs too fast due to turbo modes. +# Global switch whether to build a hardlockup detector at all. It is available +# only when the architecture supports at least one implementation. There are +# two exceptions. The hardlockup detector is never enabled on: # -config HARDLOCKUP_CHECK_TIMESTAMP - bool - +# s390: it reported many false positives there # -# arch/ can define HAVE_HARDLOCKUP_DETECTOR_ARCH to provide their own hard -# lockup detector rather than the perf based detector. +# sparc64: has a custom implementation which is not using the common +# hardlockup command line options and sysctl interface. # config HARDLOCKUP_DETECTOR bool "Detect Hard Lockups" - depends on DEBUG_KERNEL && !S390 - depends on HAVE_HARDLOCKUP_DETECTOR_PERF || HAVE_HARDLOCKUP_DETECTOR_ARCH + depends on DEBUG_KERNEL && !S390 && !HARDLOCKUP_DETECTOR_SPARC64 + depends on HAVE_HARDLOCKUP_DETECTOR_PERF || HAVE_HARDLOCKUP_DETECTOR_BUDDY || HAVE_HARDLOCKUP_DETECTOR_ARCH + imply HARDLOCKUP_DETECTOR_PERF + imply HARDLOCKUP_DETECTOR_BUDDY + imply HARDLOCKUP_DETECTOR_ARCH select LOCKUP_DETECTOR - select HARDLOCKUP_DETECTOR_PERF if HAVE_HARDLOCKUP_DETECTOR_PERF - select HARDLOCKUP_DETECTOR_ARCH if HAVE_HARDLOCKUP_DETECTOR_ARCH + help Say Y here to enable the kernel to act as a watchdog to detect hard lockups. @@ -907,6 +1079,63 @@ config HARDLOCKUP_DETECTOR chance to run. The current stack trace is displayed upon detection and the system will stay locked up. +# +# Note that arch-specific variants are always preferred. +# +config HARDLOCKUP_DETECTOR_PREFER_BUDDY + bool "Prefer the buddy CPU hardlockup detector" + depends on HARDLOCKUP_DETECTOR + depends on HAVE_HARDLOCKUP_DETECTOR_PERF && HAVE_HARDLOCKUP_DETECTOR_BUDDY + depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH + help + Say Y here to prefer the buddy hardlockup detector over the perf one. + + With the buddy detector, each CPU uses its softlockup hrtimer + to check that the next CPU is processing hrtimer interrupts by + verifying that a counter is increasing. + + This hardlockup detector is useful on systems that don't have + an arch-specific hardlockup detector or if resources needed + for the hardlockup detector are better used for other things. + +config HARDLOCKUP_DETECTOR_PERF + bool + depends on HARDLOCKUP_DETECTOR + depends on HAVE_HARDLOCKUP_DETECTOR_PERF && !HARDLOCKUP_DETECTOR_PREFER_BUDDY + depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH + select HARDLOCKUP_DETECTOR_COUNTS_HRTIMER + +config HARDLOCKUP_DETECTOR_BUDDY + bool + depends on HARDLOCKUP_DETECTOR + depends on HAVE_HARDLOCKUP_DETECTOR_BUDDY + depends on !HAVE_HARDLOCKUP_DETECTOR_PERF || HARDLOCKUP_DETECTOR_PREFER_BUDDY + depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH + select HARDLOCKUP_DETECTOR_COUNTS_HRTIMER + +config HARDLOCKUP_DETECTOR_ARCH + bool + depends on HARDLOCKUP_DETECTOR + depends on HAVE_HARDLOCKUP_DETECTOR_ARCH + help + The arch-specific implementation of the hardlockup detector will + be used. + +# +# Both the "perf" and "buddy" hardlockup detectors count hrtimer +# interrupts. This config enables functions managing this common code. +# +config HARDLOCKUP_DETECTOR_COUNTS_HRTIMER + bool + select SOFTLOCKUP_DETECTOR + +# +# Enables a timestamp based low pass filter to compensate for perf based +# hard lockup detection which runs too fast due to turbo modes. +# +config HARDLOCKUP_CHECK_TIMESTAMP + bool + config BOOTPARAM_HARDLOCKUP_PANIC bool "Panic (Reboot) On Hard Lockups" depends on HARDLOCKUP_DETECTOR @@ -918,13 +1147,6 @@ config BOOTPARAM_HARDLOCKUP_PANIC Say N if unsure. -config BOOTPARAM_HARDLOCKUP_PANIC_VALUE - int - depends on HARDLOCKUP_DETECTOR - range 0 1 - default 0 if !BOOTPARAM_HARDLOCKUP_PANIC - default 1 if BOOTPARAM_HARDLOCKUP_PANIC - config DETECT_HUNG_TASK bool "Detect Hung Tasks" depends on DEBUG_KERNEL @@ -972,13 +1194,6 @@ config BOOTPARAM_HUNG_TASK_PANIC Say N if unsure. -config BOOTPARAM_HUNG_TASK_PANIC_VALUE - int - depends on DETECT_HUNG_TASK - range 0 1 - default 0 if !BOOTPARAM_HUNG_TASK_PANIC - default 1 if BOOTPARAM_HUNG_TASK_PANIC - config WQ_WATCHDOG bool "Detect Workqueue Stalls" depends on DEBUG_KERNEL @@ -990,42 +1205,42 @@ config WQ_WATCHDOG state. This can be configured through kernel parameter "workqueue.watchdog_thresh" and its sysfs counterpart. -endmenu # "Debug lockups and hangs" - -config PANIC_ON_OOPS - bool "Panic on Oops" +config WQ_CPU_INTENSIVE_REPORT + bool "Report per-cpu work items which hog CPU for too long" + depends on DEBUG_KERNEL help - Say Y here to enable the kernel to panic when it oopses. This - has the same effect as setting oops=panic on the kernel command - line. + Say Y here to enable reporting of concurrency-managed per-cpu work + items that hog CPUs for longer than + workqueue.cpu_intensive_thresh_us. Workqueue automatically + detects and excludes them from concurrency management to prevent + them from stalling other per-cpu work items. Occassional + triggering may not necessarily indicate a problem. Repeated + triggering likely indicates that the work item should be switched + to use an unbound workqueue. + +config TEST_LOCKUP + tristate "Test module to generate lockups" + depends on m + help + This builds the "test_lockup" module that helps to make sure + that watchdogs and lockup detectors are working properly. - This feature is useful to ensure that the kernel does not do - anything erroneous after an oops which could result in data - corruption or other issues. + Depending on module parameters it could emulate soft or hard + lockup, "hung task", or locking arbitrary lock for a long time. + Also it could generate series of lockups with cooling-down periods. - Say N if unsure. + If unsure, say N. -config PANIC_ON_OOPS_VALUE - int - range 0 1 - default 0 if !PANIC_ON_OOPS - default 1 if PANIC_ON_OOPS +endmenu # "Debug lockups and hangs" -config PANIC_TIMEOUT - int "panic timeout" - default 0 - help - Set the timeout value (in seconds) until a reboot occurs when the - the kernel panics. If n = 0, then we wait forever. A timeout - value n > 0 will wait n seconds before rebooting, while a timeout - value n < 0 will reboot immediately. +menu "Scheduler Debugging" config SCHED_DEBUG bool "Collect scheduler debugging info" - depends on DEBUG_KERNEL && PROC_FS + depends on DEBUG_KERNEL && DEBUG_FS default y help - If you say Y here, the /proc/sched_debug file will be provided + If you say Y here, the /sys/kernel/debug/sched file will be provided that can help debug the scheduler. The runtime overhead of this option is minimal. @@ -1046,17 +1261,7 @@ config SCHEDSTATS application, you can say N to avoid the very slight overhead this adds. -config SCHED_STACK_END_CHECK - bool "Detect stack corruption on calls to schedule()" - depends on DEBUG_KERNEL - default n - help - This option checks for a stack overrun on calls to schedule(). - If the stack end location is found to be over written always panic as - the content of the corrupted region can no longer be trusted. - This is to ensure no erroneous behaviour occurs which could result in - data corruption or a sporadic crash at a later stage once the region - is examined. The runtime overhead introduced is minimal. +endmenu config DEBUG_TIMEKEEPING bool "Enable extra timekeeping sanity checking" @@ -1073,14 +1278,17 @@ config DEBUG_TIMEKEEPING config DEBUG_PREEMPT bool "Debug preemptible kernel" - depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT - default y + depends on DEBUG_KERNEL && PREEMPTION && TRACE_IRQFLAGS_SUPPORT help If you say Y here then the kernel will use a debug variant of the commonly used smp_processor_id() function and will print warnings if kernel code uses it in a preemption-unsafe way. Also, the kernel will detect preemption count underflows. + This option has potential to introduce high runtime overhead, + depending on workload as it triggers debugging routines for each + this_cpu operation. It should only be used for debugging purposes. + menu "Lock Debugging (spinlocks, mutexes, etc...)" config LOCK_DEBUGGING_SUPPORT @@ -1093,11 +1301,12 @@ config PROVE_LOCKING depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT select LOCKDEP select DEBUG_SPINLOCK - select DEBUG_MUTEXES + select DEBUG_MUTEXES if !PREEMPT_RT select DEBUG_RT_MUTEXES if RT_MUTEXES - select DEBUG_RWSEMS if RWSEM_SPIN_ON_OWNER + select DEBUG_RWSEMS select DEBUG_WW_MUTEX_SLOWPATH select DEBUG_LOCK_ALLOC + select PREEMPT_COUNT if !ARCH_NO_PREEMPT select TRACE_IRQFLAGS default n help @@ -1132,21 +1341,38 @@ config PROVE_LOCKING the proof of observed correctness is also maintained for an arbitrary combination of these separate locking variants. - For more details, see Documentation/locking/lockdep-design.txt. + For more details, see Documentation/locking/lockdep-design.rst. + +config PROVE_RAW_LOCK_NESTING + bool "Enable raw_spinlock - spinlock nesting checks" + depends on PROVE_LOCKING + default n + help + Enable the raw_spinlock vs. spinlock nesting checks which ensure + that the lock nesting rules for PREEMPT_RT enabled kernels are + not violated. + + NOTE: There are known nesting problems. So if you enable this + option expect lockdep splats until these problems have been fully + addressed which is work in progress. This config switch allows to + identify and analyze these problems. It will be removed and the + check permanently enabled once the main issues have been fixed. + + If unsure, select N. config LOCK_STAT bool "Lock usage statistics" depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT select LOCKDEP select DEBUG_SPINLOCK - select DEBUG_MUTEXES + select DEBUG_MUTEXES if !PREEMPT_RT select DEBUG_RT_MUTEXES if RT_MUTEXES select DEBUG_LOCK_ALLOC default n help This feature enables tracking lock contention points - For more details, see Documentation/locking/lockstat.txt + For more details, see Documentation/locking/lockstat.rst This also enables lock events required by "perf lock", subcommand of perf. @@ -1175,7 +1401,7 @@ config DEBUG_SPINLOCK config DEBUG_MUTEXES bool "Mutex debugging: basic checks" - depends on DEBUG_KERNEL + depends on DEBUG_KERNEL && !PREEMPT_RT help This feature allows mutex semantics violations to be detected and reported. @@ -1185,7 +1411,8 @@ config DEBUG_WW_MUTEX_SLOWPATH depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT select DEBUG_LOCK_ALLOC select DEBUG_SPINLOCK - select DEBUG_MUTEXES + select DEBUG_MUTEXES if !PREEMPT_RT + select DEBUG_RT_MUTEXES if PREEMPT_RT help This feature enables slowpath testing for w/w mutex users by injecting additional -EDEADLK wound/backoff cases. Together with @@ -1199,16 +1426,16 @@ config DEBUG_WW_MUTEX_SLOWPATH config DEBUG_RWSEMS bool "RW Semaphore debugging: basic checks" - depends on DEBUG_KERNEL && RWSEM_SPIN_ON_OWNER + depends on DEBUG_KERNEL help - This debugging feature allows mismatched rw semaphore locks and unlocks - to be detected and reported. + This debugging feature allows mismatched rw semaphore locks + and unlocks to be detected and reported. config DEBUG_LOCK_ALLOC bool "Lock debugging: detect incorrect freeing of live locks" depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT select DEBUG_SPINLOCK - select DEBUG_MUTEXES + select DEBUG_MUTEXES if !PREEMPT_RT select DEBUG_RT_MUTEXES if RT_MUTEXES select LOCKDEP help @@ -1223,16 +1450,56 @@ config LOCKDEP bool depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT select STACKTRACE - select FRAME_POINTER if !MIPS && !PPC && !ARM && !S390 && !MICROBLAZE && !ARC && !X86 select KALLSYMS select KALLSYMS_ALL config LOCKDEP_SMALL bool +config LOCKDEP_BITS + int "Bitsize for MAX_LOCKDEP_ENTRIES" + depends on LOCKDEP && !LOCKDEP_SMALL + range 10 30 + default 15 + help + Try increasing this value if you hit "BUG: MAX_LOCKDEP_ENTRIES too low!" message. + +config LOCKDEP_CHAINS_BITS + int "Bitsize for MAX_LOCKDEP_CHAINS" + depends on LOCKDEP && !LOCKDEP_SMALL + range 10 30 + default 16 + help + Try increasing this value if you hit "BUG: MAX_LOCKDEP_CHAINS too low!" message. + +config LOCKDEP_STACK_TRACE_BITS + int "Bitsize for MAX_STACK_TRACE_ENTRIES" + depends on LOCKDEP && !LOCKDEP_SMALL + range 10 30 + default 19 + help + Try increasing this value if you hit "BUG: MAX_STACK_TRACE_ENTRIES too low!" message. + +config LOCKDEP_STACK_TRACE_HASH_BITS + int "Bitsize for STACK_TRACE_HASH_SIZE" + depends on LOCKDEP && !LOCKDEP_SMALL + range 10 30 + default 14 + help + Try increasing this value if you need large STACK_TRACE_HASH_SIZE. + +config LOCKDEP_CIRCULAR_QUEUE_BITS + int "Bitsize for elements in circular_queue struct" + depends on LOCKDEP + range 10 30 + default 12 + help + Try increasing this value if you hit "lockdep bfs error:-1" warning due to __cq_enqueue() failure. + config DEBUG_LOCKDEP bool "Lock dependency engine debugging" depends on DEBUG_KERNEL && LOCKDEP + select DEBUG_IRQFLAGS help If you say Y here, the lock dependency engine will do additional runtime checks to debug itself, at the price @@ -1256,7 +1523,7 @@ config DEBUG_LOCKING_API_SELFTESTS Say Y here if you want the kernel to run a short self-test during bootup. The self-test checks whether common types of locking bugs are detected by debugging mechanisms or not. (if you disable - lock debugging then those bugs wont be detected of course.) + lock debugging then those bugs won't be detected of course.) The following locking APIs are covered: spinlocks, rwlocks, mutexes and rwsems. @@ -1286,14 +1553,68 @@ config WW_MUTEX_SELFTEST Say M if you want these self tests to build as a module. Say N if you are unsure. +config SCF_TORTURE_TEST + tristate "torture tests for smp_call_function*()" + depends on DEBUG_KERNEL + select TORTURE_TEST + help + This option provides a kernel module that runs torture tests + on the smp_call_function() family of primitives. The kernel + module may be built after the fact on the running kernel to + be tested, if desired. + +config CSD_LOCK_WAIT_DEBUG + bool "Debugging for csd_lock_wait(), called from smp_call_function*()" + depends on DEBUG_KERNEL + depends on 64BIT + default n + help + This option enables debug prints when CPUs are slow to respond + to the smp_call_function*() IPI wrappers. These debug prints + include the IPI handler function currently executing (if any) + and relevant stack traces. + +config CSD_LOCK_WAIT_DEBUG_DEFAULT + bool "Default csd_lock_wait() debugging on at boot time" + depends on CSD_LOCK_WAIT_DEBUG + depends on 64BIT + default n + help + This option causes the csdlock_debug= kernel boot parameter to + default to 1 (basic debugging) instead of 0 (no debugging). + endmenu # lock debugging config TRACE_IRQFLAGS + depends on TRACE_IRQFLAGS_SUPPORT bool help Enables hooks to interrupt enabling and disabling for either tracing or lock debugging. +config TRACE_IRQFLAGS_NMI + def_bool y + depends on TRACE_IRQFLAGS + depends on TRACE_IRQFLAGS_NMI_SUPPORT + +config NMI_CHECK_CPU + bool "Debugging for CPUs failing to respond to backtrace requests" + depends on DEBUG_KERNEL + depends on X86 + default n + help + Enables debug prints when a CPU fails to respond to a given + backtrace NMI. These prints provide some reasons why a CPU + might legitimately be failing to respond, for example, if it + is offline of if ignore_nmis is set. + +config DEBUG_IRQFLAGS + bool "Debug IRQ flag manipulation" + help + Enables checks for potentially unsafe enabling or disabling of + interrupts, such as calling raw_local_irq_restore() when interrupts + are enabled. + config STACKTRACE bool "Stack backtrace support" depends on STACKTRACE_SUPPORT @@ -1322,8 +1643,7 @@ config WARN_ALL_UNSEEDED_RANDOM so architecture maintainers really need to do what they can to get the CRNG seeded sooner after the system is booted. However, since users cannot do anything actionable to - address this, by default the kernel will issue only a single - warning for the first use of unseeded randomness. + address this, by default this option is disabled. Say Y here if you want to receive warnings for all uses of unseeded randomness. This will be of use primarily for @@ -1344,7 +1664,7 @@ config DEBUG_KOBJECT_RELEASE help kobjects are reference counted objects. This means that their last reference count put is not predictable, and the kobject can - live on past the point at which a driver decides to drop it's + live on past the point at which a driver decides to drop its initial reference to the kobject gained on allocation. An example of this would be a struct device which has just been unregistered. @@ -1360,21 +1680,19 @@ config DEBUG_KOBJECT_RELEASE config HAVE_DEBUG_BUGVERBOSE bool -config DEBUG_BUGVERBOSE - bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT - depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE) - default y - help - Say Y here to make BUG() panics output the file name and line number - of the BUG call as well as the EIP and oops trace. This aids - debugging but costs about 70-100K of memory. +menu "Debug kernel data structures" config DEBUG_LIST bool "Debug linked list manipulation" - depends on DEBUG_KERNEL || BUG_ON_DATA_CORRUPTION + depends on DEBUG_KERNEL + select LIST_HARDENED help - Enable this to turn on extended checks in the linked-list - walking routines. + Enable this to turn on extended checks in the linked-list walking + routines. + + This option trades better quality error reports for performance, and + is more suitable for kernel debugging. If you care about performance, + you should only enable CONFIG_LIST_HARDENED instead. If unsure, say N. @@ -1408,21 +1726,25 @@ config DEBUG_NOTIFIERS This is a relatively cheap check but if you care about maximum performance, say N. -config DEBUG_CREDENTIALS - bool "Debug credential management" - depends on DEBUG_KERNEL +config DEBUG_CLOSURES + bool "Debug closures (bcache async widgits)" + depends on CLOSURES + select DEBUG_FS help - Enable this to turn on some debug checking for credential - management. The additional code keeps track of the number of - pointers from task_structs to any given cred struct, and checks to - see that this number never exceeds the usage count of the cred - struct. + Keeps all active closures in a linked list and provides a debugfs + interface to list them, which makes it possible to see asynchronous + operations that get stuck. - Furthermore, if SELinux is enabled, this also checks that the - security pointer in the cred struct is never seen to be invalid. +config DEBUG_MAPLE_TREE + bool "Debug maple trees" + depends on DEBUG_KERNEL + help + Enable maple tree debugging information and extra validations. If unsure, say N. +endmenu + source "kernel/rcu/Kconfig.debug" config DEBUG_WQ_FORCE_RR_CPU @@ -1440,33 +1762,6 @@ config DEBUG_WQ_FORCE_RR_CPU feature by default. When enabled, memory and cache locality will be impacted. -config DEBUG_BLOCK_EXT_DEVT - bool "Force extended block device numbers and spread them" - depends on DEBUG_KERNEL - depends on BLOCK - default n - help - BIG FAT WARNING: ENABLING THIS OPTION MIGHT BREAK BOOTING ON - SOME DISTRIBUTIONS. DO NOT ENABLE THIS UNLESS YOU KNOW WHAT - YOU ARE DOING. Distros, please enable this and fix whatever - is broken. - - Conventionally, block device numbers are allocated from - predetermined contiguous area. However, extended block area - may introduce non-contiguous block device numbers. This - option forces most block device numbers to be allocated from - the extended space and spreads them to discover kernel or - userland code paths which assume predetermined contiguous - device number allocation. - - Note that turning on this debug option shuffles all the - device numbers for all IDE and SCSI devices including libata - ones, so root partition specified using device number - directly (via rdev or root=MAJ:MIN) won't work anymore. - Textual device names (root=/dev/sdXn) will continue to work. - - Say N if you are unsure. - config CPU_HOTPLUG_STATE_CONTROL bool "Enable CPU hotplug state control" depends on DEBUG_KERNEL @@ -1480,6 +1775,112 @@ config CPU_HOTPLUG_STATE_CONTROL Say N if your are unsure. +config LATENCYTOP + bool "Latency measuring infrastructure" + depends on DEBUG_KERNEL + depends on STACKTRACE_SUPPORT + depends on PROC_FS + depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86 + select KALLSYMS + select KALLSYMS_ALL + select STACKTRACE + select SCHEDSTATS + help + Enable this option if you want to use the LatencyTOP tool + to find out which userspace is blocking on what kernel operations. + +config DEBUG_CGROUP_REF + bool "Disable inlining of cgroup css reference count functions" + depends on DEBUG_KERNEL + depends on CGROUPS + depends on KPROBES + default n + help + Force cgroup css reference count functions to not be inlined so + that they can be kprobed for debugging. + +source "kernel/trace/Kconfig" + +config PROVIDE_OHCI1394_DMA_INIT + bool "Remote debugging over FireWire early on boot" + depends on PCI && X86 + help + If you want to debug problems which hang or crash the kernel early + on boot and the crashing machine has a FireWire port, you can use + this feature to remotely access the memory of the crashed machine + over FireWire. This employs remote DMA as part of the OHCI1394 + specification which is now the standard for FireWire controllers. + + With remote DMA, you can monitor the printk buffer remotely using + firescope and access all memory below 4GB using fireproxy from gdb. + Even controlling a kernel debugger is possible using remote DMA. + + Usage: + + If ohci1394_dma=early is used as boot parameter, it will initialize + all OHCI1394 controllers which are found in the PCI config space. + + As all changes to the FireWire bus such as enabling and disabling + devices cause a bus reset and thereby disable remote DMA for all + devices, be sure to have the cable plugged and FireWire enabled on + the debugging host before booting the debug target for debugging. + + This code (~1k) is freed after boot. By then, the firewire stack + in charge of the OHCI-1394 controllers should be used instead. + + See Documentation/core-api/debugging-via-ohci1394.rst for more information. + +source "samples/Kconfig" + +config ARCH_HAS_DEVMEM_IS_ALLOWED + bool + +config STRICT_DEVMEM + bool "Filter access to /dev/mem" + depends on MMU && DEVMEM + depends on ARCH_HAS_DEVMEM_IS_ALLOWED || GENERIC_LIB_DEVMEM_IS_ALLOWED + default y if PPC || X86 || ARM64 + help + If this option is disabled, you allow userspace (root) access to all + of memory, including kernel and userspace memory. Accidental + access to this is obviously disastrous, but specific access can + be used by people debugging the kernel. Note that with PAT support + enabled, even in this case there are restrictions on /dev/mem + use due to the cache aliasing requirements. + + If this option is switched on, and IO_STRICT_DEVMEM=n, the /dev/mem + file only allows userspace access to PCI space and the BIOS code and + data regions. This is sufficient for dosemu and X and all common + users of /dev/mem. + + If in doubt, say Y. + +config IO_STRICT_DEVMEM + bool "Filter I/O access to /dev/mem" + depends on STRICT_DEVMEM + help + If this option is disabled, you allow userspace (root) access to all + io-memory regardless of whether a driver is actively using that + range. Accidental access to this is obviously disastrous, but + specific access can be used by people debugging kernel drivers. + + If this option is switched on, the /dev/mem file only allows + userspace access to *idle* io-memory ranges (see /proc/iomem) This + may break traditional users of /dev/mem (dosemu, legacy X, etc...) + if the driver using a given range cannot be disabled. + + If in doubt, say Y. + +menu "$(SRCARCH) Debugging" + +source "arch/$(SRCARCH)/Kconfig.debug" + +endmenu + +menu "Kernel Testing and Coverage" + +source "lib/kunit/Kconfig" + config NOTIFIER_ERROR_INJECTION tristate "Notifier error injection" depends on DEBUG_KERNEL @@ -1556,8 +1957,14 @@ config NETDEV_NOTIFIER_ERROR_INJECT If unsure, say N. config FUNCTION_ERROR_INJECTION - def_bool y + bool "Fault-injections of functions" depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES + help + Add fault injections into various functions that are annotated with + ALLOW_ERROR_INJECTION() in the kernel. BPF may also modify the return + value of these functions. This is useful to test error paths of code. + + If unsure, say N config FAULT_INJECTION bool "Fault-injection framework" @@ -1569,16 +1976,22 @@ config FAULT_INJECTION config FAILSLAB bool "Fault-injection capability for kmalloc" depends on FAULT_INJECTION - depends on SLAB || SLUB help Provide fault-injection capability for kmalloc. config FAIL_PAGE_ALLOC - bool "Fault-injection capabilitiy for alloc_pages()" + bool "Fault-injection capability for alloc_pages()" depends on FAULT_INJECTION help Provide fault-injection capability for alloc_pages(). +config FAULT_INJECTION_USERCOPY + bool "Fault injection capability for usercopy functions" + depends on FAULT_INJECTION + help + Provides fault-injection capability to inject failures + in usercopy functions (copy_from_user(), get_user(), ...). + config FAIL_MAKE_REQUEST bool "Fault-injection capability for disk IO" depends on FAULT_INJECTION && BLOCK @@ -1594,7 +2007,7 @@ config FAIL_IO_TIMEOUT thus exercising the error handling. Only works with drivers that use the generic timeout handling, - for others it wont do anything. + for others it won't do anything. config FAIL_FUTEX bool "Fault-injection capability for futexes" @@ -1629,60 +2042,88 @@ config FAIL_MMC_REQUEST and to test how the mmc host driver handles retries from the block device. +config FAIL_SUNRPC + bool "Fault-injection capability for SunRPC" + depends on FAULT_INJECTION_DEBUG_FS && SUNRPC_DEBUG + help + Provide fault-injection capability for SunRPC and + its consumers. + +config FAULT_INJECTION_CONFIGFS + bool "Configfs interface for fault-injection capabilities" + depends on FAULT_INJECTION + select CONFIGFS_FS + help + This option allows configfs-based drivers to dynamically configure + fault-injection via configfs. Each parameter for driver-specific + fault-injection can be made visible as a configfs attribute in a + configfs group. + + config FAULT_INJECTION_STACKTRACE_FILTER bool "stacktrace filter for fault-injection capabilities" - depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT - depends on !X86_64 + depends on FAULT_INJECTION + depends on (FAULT_INJECTION_DEBUG_FS || FAULT_INJECTION_CONFIGFS) && STACKTRACE_SUPPORT select STACKTRACE - select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM && !ARC && !X86 + depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86 help Provide stacktrace filter for fault-injection capabilities -config LATENCYTOP - bool "Latency measuring infrastructure" - depends on DEBUG_KERNEL - depends on STACKTRACE_SUPPORT - depends on PROC_FS - select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM && !ARC && !X86 - select KALLSYMS - select KALLSYMS_ALL - select STACKTRACE - select SCHEDSTATS - select SCHED_DEBUG +config ARCH_HAS_KCOV + bool help - Enable this option if you want to use the LatencyTOP tool - to find out which userspace is blocking on what kernel operations. - -source "kernel/trace/Kconfig" + An architecture should select this when it can successfully + build and run with CONFIG_KCOV. This typically requires + disabling instrumentation for some early boot code. -config PROVIDE_OHCI1394_DMA_INIT - bool "Remote debugging over FireWire early on boot" - depends on PCI && X86 - help - If you want to debug problems which hang or crash the kernel early - on boot and the crashing machine has a FireWire port, you can use - this feature to remotely access the memory of the crashed machine - over FireWire. This employs remote DMA as part of the OHCI1394 - specification which is now the standard for FireWire controllers. +config CC_HAS_SANCOV_TRACE_PC + def_bool $(cc-option,-fsanitize-coverage=trace-pc) - With remote DMA, you can monitor the printk buffer remotely using - firescope and access all memory below 4GB using fireproxy from gdb. - Even controlling a kernel debugger is possible using remote DMA. - Usage: +config KCOV + bool "Code coverage for fuzzing" + depends on ARCH_HAS_KCOV + depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS + depends on !ARCH_WANTS_NO_INSTR || HAVE_NOINSTR_HACK || \ + GCC_VERSION >= 120000 || CLANG_VERSION >= 130000 + select DEBUG_FS + select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC + select OBJTOOL if HAVE_NOINSTR_HACK + help + KCOV exposes kernel code coverage information in a form suitable + for coverage-guided fuzzing (randomized testing). - If ohci1394_dma=early is used as boot parameter, it will initialize - all OHCI1394 controllers which are found in the PCI config space. + For more details, see Documentation/dev-tools/kcov.rst. - As all changes to the FireWire bus such as enabling and disabling - devices cause a bus reset and thereby disable remote DMA for all - devices, be sure to have the cable plugged and FireWire enabled on - the debugging host before booting the debug target for debugging. +config KCOV_ENABLE_COMPARISONS + bool "Enable comparison operands collection by KCOV" + depends on KCOV + depends on $(cc-option,-fsanitize-coverage=trace-cmp) + help + KCOV also exposes operands of every comparison in the instrumented + code along with operand sizes and PCs of the comparison instructions. + These operands can be used by fuzzing engines to improve the quality + of fuzzing coverage. - This code (~1k) is freed after boot. By then, the firewire stack - in charge of the OHCI-1394 controllers should be used instead. +config KCOV_INSTRUMENT_ALL + bool "Instrument all code by default" + depends on KCOV + default y + help + If you are doing generic system call fuzzing (like e.g. syzkaller), + then you will want to instrument the whole kernel and you should + say y here. If you are doing more targeted fuzzing (like e.g. + filesystem fuzzing with AFL) then you will want to enable coverage + for more specific subsets of files, and should say n here. - See Documentation/debugging-via-ohci1394.txt for more information. +config KCOV_IRQ_AREA_SIZE + hex "Size of interrupt coverage collection area in words" + depends on KCOV + default 0x40000 + help + KCOV uses preallocated per-cpu areas to collect coverage from + soft interrupts. This specifies the size of those areas in the + number of unsigned long words. menuconfig RUNTIME_TESTING_MENU bool "Runtime Testing" @@ -1690,6 +2131,41 @@ menuconfig RUNTIME_TESTING_MENU if RUNTIME_TESTING_MENU +config TEST_DHRY + tristate "Dhrystone benchmark test" + help + Enable this to include the Dhrystone 2.1 benchmark. This test + calculates the number of Dhrystones per second, and the number of + DMIPS (Dhrystone MIPS) obtained when the Dhrystone score is divided + by 1757 (the number of Dhrystones per second obtained on the VAX + 11/780, nominally a 1 MIPS machine). + + To run the benchmark, it needs to be enabled explicitly, either from + the kernel command line (when built-in), or from userspace (when + built-in or modular. + + Run once during kernel boot: + + test_dhry.run + + Set number of iterations from kernel command line: + + test_dhry.iterations=<n> + + Set number of iterations from userspace: + + echo <n> > /sys/module/test_dhry/parameters/iterations + + Trigger manual run from userspace: + + echo y > /sys/module/test_dhry/parameters/run + + If the number of iterations is <= 0, the test will devise a suitable + number of iterations (test runs for at least 2s) automatically. + This process takes ca. 4s. + + If unsure, say N. + config LKDTM tristate "Linux Kernel Dump Test Tool Module" depends on DEBUG_FS @@ -1701,11 +2177,24 @@ config LKDTM called lkdtm. Documentation on how to use the module can be found in - Documentation/fault-injection/provoke-crashes.txt + Documentation/fault-injection/provoke-crashes.rst + +config CPUMASK_KUNIT_TEST + tristate "KUnit test for cpumask" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Enable to turn on cpumask tests, running at boot or module load time. + + For more information on KUnit and unit tests in general, please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. config TEST_LIST_SORT - tristate "Linked list sorting test" - depends on DEBUG_KERNEL || m + tristate "Linked list sorting test" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS help Enable this to turn on 'list_sort()' function test. This test is executed only once during system boot (so affects only boot time), @@ -1713,19 +2202,55 @@ config TEST_LIST_SORT If unsure, say N. -config TEST_SORT - tristate "Array-based sort test" +config TEST_MIN_HEAP + tristate "Min heap test" depends on DEBUG_KERNEL || m help + Enable this to turn on min heap function tests. This test is + executed only once during system boot (so affects only boot time), + or at module load time. + + If unsure, say N. + +config TEST_SORT + tristate "Array-based sort test" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help This option enables the self-test function of 'sort()' at boot, or at module load time. If unsure, say N. +config TEST_DIV64 + tristate "64bit/32bit division and modulo test" + depends on DEBUG_KERNEL || m + help + Enable this to turn on 'do_div()' function test. This test is + executed only once during system boot (so affects only boot time), + or at module load time. + + If unsure, say N. + +config TEST_IOV_ITER + tristate "Test iov_iter operation" if !KUNIT_ALL_TESTS + depends on KUNIT + depends on MMU + default KUNIT_ALL_TESTS + help + Enable this to turn on testing of the operation of the I/O iterator + (iov_iter). This test is executed only once during system boot (so + affects only boot time), or at module load time. + + If unsure, say N. + config KPROBES_SANITY_TEST - bool "Kprobes sanity tests" + tristate "Kprobes sanity tests" if !KUNIT_ALL_TESTS depends on DEBUG_KERNEL depends on KPROBES + depends on KUNIT + select STACKTRACE if ARCH_CORRECT_STACKTRACE_ON_KRETPROBE + default KUNIT_ALL_TESTS help This option provides for testing basic kprobes functionality on boot. Samples of kprobe and kretprobe are inserted and @@ -1733,6 +2258,18 @@ config KPROBES_SANITY_TEST Say N if you are unsure. +config FPROBE_SANITY_TEST + bool "Self test for fprobe" + depends on DEBUG_KERNEL + depends on FPROBE + depends on KUNIT=y + help + This option will enable testing the fprobe when the system boot. + A series of tests are made to verify that the fprobe is functioning + properly. + + Say N if you are unsure. + config BACKTRACE_SELF_TEST tristate "Self test for the backtrace code" depends on DEBUG_KERNEL @@ -1747,6 +2284,16 @@ config BACKTRACE_SELF_TEST Say N if you are unsure. +config TEST_REF_TRACKER + tristate "Self test for reference tracker" + depends on DEBUG_KERNEL && STACKTRACE_SUPPORT + select REF_TRACKER + help + This option provides a kernel module performing tests + using reference tracker infrastructure. + + Say N if you are unsure. + config RBTREE_TEST tristate "Red-Black tree test" depends on DEBUG_KERNEL @@ -1754,6 +2301,18 @@ config RBTREE_TEST A benchmark measuring the performance of the rbtree library. Also includes rbtree invariant checks. +config REED_SOLOMON_TEST + tristate "Reed-Solomon library test" + depends on DEBUG_KERNEL || m + select REED_SOLOMON + select REED_SOLOMON_ENC16 + select REED_SOLOMON_DEC16 + help + This option enables the self-test function of rslib at boot, + or at module load time. + + If unsure, say N. + config INTERVAL_TREE_TEST tristate "Interval tree test" depends on DEBUG_KERNEL @@ -1782,7 +2341,7 @@ config ASYNC_RAID6_TEST tristate "Self test for hardware accelerated raid6 recovery" depends on ASYNC_RAID6_RECOV select ASYNC_MEMCPY - ---help--- + help This is a one-shot self test that permutes through the recovery of all the possible two disk failure scenarios for a N-disk array. Recovery is performed with the asynchronous @@ -1794,18 +2353,21 @@ config ASYNC_RAID6_TEST config TEST_HEXDUMP tristate "Test functions located in the hexdump module at runtime" +config STRING_SELFTEST + tristate "Test string functions at runtime" + config TEST_STRING_HELPERS tristate "Test functions located in the string_helpers module at runtime" -config TEST_STRSCPY - tristate "Test strscpy*() family of functions at runtime" - config TEST_KSTRTOX tristate "Test kstrto*() family of functions at runtime" config TEST_PRINTF tristate "Test printf() family of functions at runtime" +config TEST_SCANF + tristate "Test scanf() family of functions at runtime" + config TEST_BITMAP tristate "Test bitmap_*() family of functions at runtime" help @@ -1813,21 +2375,20 @@ config TEST_BITMAP If unsure, say N. -config TEST_BITFIELD - tristate "Test bitfield functions at runtime" - help - Enable this option to test the bitfield functions at boot. - - If unsure, say N. - config TEST_UUID tristate "Test functions located in the uuid module at runtime" config TEST_XARRAY tristate "Test the XArray code at runtime" -config TEST_OVERFLOW - tristate "Test check_*_overflow() functions at runtime" +config TEST_MAPLE_TREE + tristate "Test the Maple Tree code at runtime or module load" + help + Enable this option to test the maple tree code functions at boot, or + when the module is loaded. Enable "Debug Maple Trees" will enable + more verbose output on failures. + + If unsure, say N. config TEST_RHASHTABLE tristate "Perform selftest on resizable hash table" @@ -1836,16 +2397,6 @@ config TEST_RHASHTABLE If unsure, say N. -config TEST_HASH - tristate "Perform selftest on hash functions" - help - Enable this option to test the kernel's integer (<linux/hash.h>), - string (<linux/stringhash.h>), and siphash (<linux/siphash.h>) - hash functions on boot (or module load). - - This is intended to help people writing architecture-specific - optimized versions. If unsure, say N. - config TEST_IDA tristate "Perform selftest on IDA functions" @@ -1858,6 +2409,14 @@ config TEST_PARMAN If unsure, say N. +config TEST_IRQ_TIMINGS + bool "IRQ timings selftest" + depends on IRQ_TIMINGS + help + Enable this option to test the irq timings code on boot. + + If unsure, say N. + config TEST_LKM tristate "Test module loading with 'hello world' module" depends on m @@ -1871,6 +2430,19 @@ config TEST_LKM If unsure, say N. +config TEST_BITOPS + tristate "Test module for compilation of bitops operations" + depends on m + help + This builds the "test_bitops" module that is much like the + TEST_LKM module except that it does a basic exercise of the + set/clear_bit macros and get_count_order/long to make sure there are + no compiler warnings from C=1 sparse checker or -Wextra + compilations. It has no dependencies and doesn't run or load unless + explicitly requested by name. for example: modprobe test_bitops. + + If unsure, say N. + config TEST_VMALLOC tristate "Test module for stress/performance analysis of vmalloc allocator" default n @@ -1909,6 +2481,15 @@ config TEST_BPF If unsure, say N. +config TEST_BLACKHOLE_DEV + tristate "Test blackhole netdev functionality" + depends on m && NET + help + This builds the "test_blackhole_dev" module that validates the + data path through this blackhole netdev. + + If unsure, say N. + config FIND_BIT_BENCHMARK tristate "Test find_bit functions" help @@ -1939,6 +2520,273 @@ config TEST_SYSCTL If unsure, say N. +config BITFIELD_KUNIT + tristate "KUnit test bitfield functions at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Enable this option to test the bitfield functions at boot. + + KUnit tests run during boot and output the results to the debug log + in TAP format (http://testanything.org/). Only useful for kernel devs + running the KUnit test harness, and not intended for inclusion into a + production build. + + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config CHECKSUM_KUNIT + tristate "KUnit test checksum functions at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Enable this option to test the checksum functions at boot. + + KUnit tests run during boot and output the results to the debug log + in TAP format (http://testanything.org/). Only useful for kernel devs + running the KUnit test harness, and not intended for inclusion into a + production build. + + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config HASH_KUNIT_TEST + tristate "KUnit Test for integer hash functions" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Enable this option to test the kernel's string (<linux/stringhash.h>), and + integer (<linux/hash.h>) hash functions on boot. + + KUnit tests run during boot and output the results to the debug log + in TAP format (https://testanything.org/). Only useful for kernel devs + running the KUnit test harness, and not intended for inclusion into a + production build. + + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + This is intended to help people writing architecture-specific + optimized versions. If unsure, say N. + +config RESOURCE_KUNIT_TEST + tristate "KUnit test for resource API" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the resource API unit test. + Tests the logic of API provided by resource.c and ioport.h. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config SYSCTL_KUNIT_TEST + tristate "KUnit test for sysctl" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the proc sysctl unit test, which runs on boot. + Tests the API contract and implementation correctness of sysctl. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config LIST_KUNIT_TEST + tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the linked list KUnit test suite. + It tests that the API and basic functionality of the list_head type + and associated macros. + + KUnit tests run during boot and output the results to the debug log + in TAP format (https://testanything.org/). Only useful for kernel devs + running the KUnit test harness, and not intended for inclusion into a + production build. + + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config HASHTABLE_KUNIT_TEST + tristate "KUnit Test for Kernel Hashtable structures" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the hashtable KUnit test suite. + It tests the basic functionality of the API defined in + include/linux/hashtable.h. For more information on KUnit and + unit tests in general please refer to the KUnit documentation + in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config LINEAR_RANGES_TEST + tristate "KUnit test for linear_ranges" + depends on KUNIT + select LINEAR_RANGES + help + This builds the linear_ranges unit test, which runs on boot. + Tests the linear_ranges logic correctness. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config CMDLINE_KUNIT_TEST + tristate "KUnit test for cmdline API" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the cmdline API unit test. + Tests the logic of API provided by cmdline.c. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config BITS_TEST + tristate "KUnit test for bits.h" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + This builds the bits unit test. + Tests the logic of macros defined in bits.h. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config SLUB_KUNIT_TEST + tristate "KUnit test for SLUB cache error detection" if !KUNIT_ALL_TESTS + depends on SLUB_DEBUG && KUNIT + default KUNIT_ALL_TESTS + help + This builds SLUB allocator unit test. + Tests SLUB cache debugging functionality. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config RATIONAL_KUNIT_TEST + tristate "KUnit test for rational.c" if !KUNIT_ALL_TESTS + depends on KUNIT && RATIONAL + default KUNIT_ALL_TESTS + help + This builds the rational math unit test. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config MEMCPY_KUNIT_TEST + tristate "Test memcpy(), memmove(), and memset() functions at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Builds unit tests for memcpy(), memmove(), and memset() functions. + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config MEMCPY_SLOW_KUNIT_TEST + bool "Include exhaustive memcpy tests" + depends on MEMCPY_KUNIT_TEST + default y + help + Some memcpy tests are quite exhaustive in checking for overlaps + and bit ranges. These can be very slow, so they are split out + as a separate config, in case they need to be disabled. + + Note this config option will be replaced by the use of KUnit test + attributes. + +config IS_SIGNED_TYPE_KUNIT_TEST + tristate "Test is_signed_type() macro" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Builds unit tests for the is_signed_type() macro. + + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config OVERFLOW_KUNIT_TEST + tristate "Test check_*_overflow() functions at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Builds unit tests for the check_*_overflow(), size_*(), allocation, and + related functions. + + For more information on KUnit and unit tests in general please refer + to the KUnit documentation in Documentation/dev-tools/kunit/. + + If unsure, say N. + +config STACKINIT_KUNIT_TEST + tristate "Test level of stack variable initialization" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Test if the kernel is zero-initializing stack variables and + padding. Coverage is controlled by compiler flags, + CONFIG_INIT_STACK_ALL_PATTERN, CONFIG_INIT_STACK_ALL_ZERO, + CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF, + or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL. + +config FORTIFY_KUNIT_TEST + tristate "Test fortified str*() and mem*() function internals at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT && FORTIFY_SOURCE + default KUNIT_ALL_TESTS + help + Builds unit tests for checking internals of FORTIFY_SOURCE as used + by the str*() and mem*() family of functions. For testing runtime + traps of FORTIFY_SOURCE, see LKDTM's "FORTIFY_*" tests. + +config HW_BREAKPOINT_KUNIT_TEST + bool "Test hw_breakpoint constraints accounting" if !KUNIT_ALL_TESTS + depends on HAVE_HW_BREAKPOINT + depends on KUNIT=y + default KUNIT_ALL_TESTS + help + Tests for hw_breakpoint constraints accounting. + + If unsure, say N. + +config STRCAT_KUNIT_TEST + tristate "Test strcat() family of functions at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + +config STRSCPY_KUNIT_TEST + tristate "Test strscpy*() family of functions at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + +config SIPHASH_KUNIT_TEST + tristate "Perform selftest on siphash functions" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Enable this option to test the kernel's siphash (<linux/siphash.h>) hash + functions on boot (or module load). + + This is intended to help people writing architecture-specific + optimized versions. If unsure, say N. + config TEST_UDELAY tristate "udelay test driver" help @@ -1955,11 +2803,22 @@ config TEST_STATIC_KEYS If unsure, say N. +config TEST_DYNAMIC_DEBUG + tristate "Test DYNAMIC_DEBUG" + depends on DYNAMIC_DEBUG + help + This module registers a tracer callback to count enabled + pr_debugs in a 'do_debugging' function, then alters their + enablements, calls the function, and compares counts. + + If unsure, say N. + config TEST_KMOD tristate "kmod stress tester" depends on m depends on NETDEVICES && NET_CORE && INET # for TUN depends on BLOCK + depends on PAGE_SIZE_LESS_THAN_256KB # for BTRFS select TEST_LKM select XFS_FS select TUN @@ -2029,85 +2888,162 @@ config TEST_OBJAGG Enable this option to test object aggregation manager on boot (or module load). +config TEST_MEMINIT + tristate "Test heap/page initialization" + help + Test if the kernel is zero-initializing heap and page allocations. + This can be useful to test init_on_alloc and init_on_free features. -config TEST_STACKINIT - tristate "Test level of stack variable initialization" + If unsure, say N. + +config TEST_HMM + tristate "Test HMM (Heterogeneous Memory Management)" + depends on TRANSPARENT_HUGEPAGE + depends on DEVICE_PRIVATE + select HMM_MIRROR + select MMU_NOTIFIER help - Test if the kernel is zero-initializing stack variables and - padding. Coverage is controlled by compiler flags, - CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF, - or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL. + This is a pseudo device driver solely for testing HMM. + Say M here if you want to build the HMM test module. + Doing so will allow you to run tools/testing/selftest/vm/hmm-tests. + + If unsure, say N. + +config TEST_FREE_PAGES + tristate "Test freeing pages" + help + Test that a memory leak does not occur due to a race between + freeing a block of pages and a speculative page reference. + Loading this module is safe if your kernel has the bug fixed. + If the bug is not fixed, it will leak gigabytes of memory and + probably OOM your system. + +config TEST_FPU + tristate "Test floating point operations in kernel space" + depends on X86 && !KCOV_INSTRUMENT_ALL + help + Enable this option to add /sys/kernel/debug/selftest_helpers/test_fpu + which will trigger a sequence of floating point operations. This is used + for self-testing floating point control register setting in + kernel_fpu_begin(). + + If unsure, say N. + +config TEST_CLOCKSOURCE_WATCHDOG + tristate "Test clocksource watchdog in kernel space" + depends on CLOCKSOURCE_WATCHDOG + help + Enable this option to create a kernel module that will trigger + a test of the clocksource watchdog. This module may be loaded + via modprobe or insmod in which case it will run upon being + loaded, or it may be built in, in which case it will run + shortly after boot. + + If unsure, say N. + +config TEST_OBJPOOL + tristate "Test module for correctness and stress of objpool" + default n + depends on m && DEBUG_KERNEL + help + This builds the "test_objpool" module that should be used for + correctness verification and concurrent testings of objects + allocation and reclamation. If unsure, say N. endif # RUNTIME_TESTING_MENU +config ARCH_USE_MEMTEST + bool + help + An architecture should select this when it uses early_memtest() + during boot process. + config MEMTEST bool "Memtest" - ---help--- + depends on ARCH_USE_MEMTEST + help This option adds a kernel parameter 'memtest', which allows memtest - to be set. + to be set and executed. memtest=0, mean disabled; -- default memtest=1, mean do 1 test pattern; ... memtest=17, mean do 17 test patterns. If you are unsure how to answer this question, answer N. -config BUG_ON_DATA_CORRUPTION - bool "Trigger a BUG when data corruption is detected" - select DEBUG_LIST + + +config HYPERV_TESTING + bool "Microsoft Hyper-V driver testing" + default n + depends on HYPERV && DEBUG_FS + help + Select this option to enable Hyper-V vmbus testing. + +endmenu # "Kernel Testing and Coverage" + +menu "Rust hacking" + +config RUST_DEBUG_ASSERTIONS + bool "Debug assertions" + depends on RUST help - Select this option if the kernel should BUG when it encounters - data corruption in kernel memory structures when they get checked - for validity. + Enables rustc's `-Cdebug-assertions` codegen option. + + This flag lets you turn `cfg(debug_assertions)` conditional + compilation on or off. This can be used to enable extra debugging + code in development but not in production. For example, it controls + the behavior of the standard library's `debug_assert!` macro. + + Note that this will apply to all Rust code, including `core`. If unsure, say N. -source "samples/Kconfig" +config RUST_OVERFLOW_CHECKS + bool "Overflow checks" + default y + depends on RUST + help + Enables rustc's `-Coverflow-checks` codegen option. -source "lib/Kconfig.kgdb" + This flag allows you to control the behavior of runtime integer + overflow. When overflow-checks are enabled, a Rust panic will occur + on overflow. -source "lib/Kconfig.ubsan" + Note that this will apply to all Rust code, including `core`. -config ARCH_HAS_DEVMEM_IS_ALLOWED - bool + If unsure, say Y. -config STRICT_DEVMEM - bool "Filter access to /dev/mem" - depends on MMU && DEVMEM - depends on ARCH_HAS_DEVMEM_IS_ALLOWED - default y if PPC || X86 || ARM64 - ---help--- - If this option is disabled, you allow userspace (root) access to all - of memory, including kernel and userspace memory. Accidental - access to this is obviously disastrous, but specific access can - be used by people debugging the kernel. Note that with PAT support - enabled, even in this case there are restrictions on /dev/mem - use due to the cache aliasing requirements. +config RUST_BUILD_ASSERT_ALLOW + bool "Allow unoptimized build-time assertions" + depends on RUST + help + Controls how are `build_error!` and `build_assert!` handled during build. - If this option is switched on, and IO_STRICT_DEVMEM=n, the /dev/mem - file only allows userspace access to PCI space and the BIOS code and - data regions. This is sufficient for dosemu and X and all common - users of /dev/mem. + If calls to them exist in the binary, it may indicate a violated invariant + or that the optimizer failed to verify the invariant during compilation. - If in doubt, say Y. + This should not happen, thus by default the build is aborted. However, + as an escape hatch, you can choose Y here to ignore them during build + and let the check be carried at runtime (with `panic!` being called if + the check fails). -config IO_STRICT_DEVMEM - bool "Filter I/O access to /dev/mem" - depends on STRICT_DEVMEM - ---help--- - If this option is disabled, you allow userspace (root) access to all - io-memory regardless of whether a driver is actively using that - range. Accidental access to this is obviously disastrous, but - specific access can be used by people debugging kernel drivers. + If unsure, say N. - If this option is switched on, the /dev/mem file only allows - userspace access to *idle* io-memory ranges (see /proc/iomem) This - may break traditional users of /dev/mem (dosemu, legacy X, etc...) - if the driver using a given range cannot be disabled. +config RUST_KERNEL_DOCTESTS + bool "Doctests for the `kernel` crate" if !KUNIT_ALL_TESTS + depends on RUST && KUNIT=y + default KUNIT_ALL_TESTS + help + This builds the documentation tests of the `kernel` crate + as KUnit tests. - If in doubt, say Y. + For more information on KUnit and unit tests in general, + please refer to the KUnit documentation in Documentation/dev-tools/kunit/. -source "arch/$(SRCARCH)/Kconfig.debug" + If unsure, say N. + +endmenu # "Rust" endmenu # Kernel hacking |